Map showing Earth’ s main lithospheric plates and
some of the world’s active volcanoes (triangles)
During the past three decades, shallow- to intermediate-depth research wells have been drilled in the Imperial Valley (the Salton Sea, California, Scientific Drilling Project), at the Inyo Domes, California, in the Valles Caldera, New Mexico, and in the Cascade Range of the Pacific Northwest. In addition, reconnaissance-style drilling to determine heat flow and hydrologic characteristics was completed over much of the Western United States. The U.S. Geological Survey (USGS) participated in most of these multidisciplinary, multiagency projects. Among them are the U.S. Department of Energy’s (DOE) Long Valley Caldera Exploratory Well (LVEW), California, support for USGS projects in Hawai‘i (funded by the National Science Foundation), and multiagency projects at The Geysers, California. Foreign projects include those at Soultz sous-Forêt (France), Iceland, Tyrniauz (Russia), and several projects in Japan (for example, Kakkonda). USGS personnel were involved in the planning of scientific experiments at each of these sites.